DE 197 32 650 A1 describes a pyromechanical disconnecting device having a housing in which an electrical conductor is arranged, having a cutting plunger and a cutting chisel made of plastic arranged thereon for severing the electrical conductor, and having a pyrotechnic igniter in which a pyrotechnic charge for driving the cutting plunger is arranged, the cutting chisel having an edge that slides along a mating edge of the housing or of a component of the housing when the cutting plunger or the cutting chisel is driven and when the electrical conductor is severed.
Disconnecting devices of the stated type can be used, for example, to interrupt the supply of current into the onboard network of a motor vehicle. These disconnecting devices are triggered in case of accident so that the supply of current is interrupted and the danger of fire is thereby diminished.
It is a drawback that the cutting power (severance of an electrical conductor with a given cross section) remains limited because of the strength properties of the cutting chisel made of plastic.
If a cutting chisel and the cutting edge are made as a unit, for example of ceramic, this has a negative impact on component costs.